Chemical Evolution in VeLLOs

نویسنده

  • Jeong-Eun Lee
چکیده

A new type of object called “Very Low Luminosity Objects (VeLLOs)” has been discovered by the Spitzer Space Telescope. VeLLOs might be substellar objects forming by accretion. However, some VeLLOs are associated with strong outflows, indicating the previous existence of massive accretion. The thermal history, which significantly affects the chemistry, between substellar objects with a continuous low accretion rate and objects in a quiescent phase after massive accretion (outburst) must be greatly different. In this study, the chemical evolution has been calculated in an episodic accretion model to show that CO and N2H + have a relation different from starless cores or Class 0/I objects. Furthermore, the CO2 ice feature at 15.2 μmm will be a good tracer of the thermal process in VeLLOs. Subject headings: ISM: astrochemistry – ISM: molecules – stars: formation

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Well Placement Optimization Using Differential Evolution Algorithm

Determining the optimal location of wells with the aid of an automated search algorithm is a significant and difficult step in the reservoir development process. It is a computationally intensive task due to the large number of simulation runs required. Therefore,the key issue to such automatic optimization is development of algorithms that can find acceptable solutions with a minimum numbe...

متن کامل

Spatial evolution of the physico-chemical, organoleptic and bacteriological properties of a municipal artificial lake

This study is a contribution to the study of the spatial evolution of the properties of the municipal lake of Yaounde-Cameroon. The objective was the characterization of the physico-chemical, bacteriological and organoleptic parameters of water of this lake in order to provide the scientifically exploitable data. To understand the sources and the evolution of the pollution of this lake, we carr...

متن کامل

MAMBO Mapping of Spitzer c2d Small Clouds and Cores

Aims. To study the structure of nearby (< 500 pc) dense starless and star-forming cores with the particular goal to identify and understand evolutionary trends in core properties, and to explore the nature of Very Low Luminosity Objects (≤ 0.1 L⊙; VeLLOs). Methods. Using the MAMBO bolometer array, we create maps unusually sensitive to faint (few mJy per beam) extended (≈ 5′) thermal dust contin...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2008